In addition to abundant digital television programs, broadcast television operators have to frequently offer personalized, bi-directionally interactive, and development-sustainable digital television data services in order to attract the subscribers, to boost the growth of the number of digital television subscribers, and to excavate new profit increasing points.
In the field of digital television, a digital television receiving device provider and a digital television service provider are usually not the same entity. However, their software is closely linked with each other on a digital television receiving device and neither is dispensable. The software from the digital television receiving device provider is oriented to providing fundamental and hardware-level software operation platforms, for example, providing a stable operating system platform, resource management, hardware driver, image decoding, and screen displaying. The software from the digital television service provider is oriented to a secondary development on the basis of the platforms provided by the digital television receiving device provider, i.e., providing digital television data services such as Multimedia Messaging Service, Short Message Service, stock information service, and information consultation, according to the requirements of the broadcast operators. The different orientations bring about different requirements for software upgrades.
Digital television receiving device provider software currently available in the market usually includes three parts, such as system terminal software (i.e. digital television receiving device software or set-top box terminal software), service software, and interface adaptation software. After being processed by a compiler and a linker, these three parts are stored as a whole in a nonvolatile memory in a digital television receiving device under certain rules. Any partial modification to data in one of the three parts regardless of the other two parts may cause a system collapse during running. Therefore, when any of the three parts needs an upgrade, a Makefile has to be re-created. The three parts have to be upgraded together. FIG. 1 shows the principle of a conventional upgrade solution.
When a service provider requires to upgrade his software, the conventional upgrade solution executes the following steps.
(A) A compiler coordinated with the CPU of the digital television receiving device is obtained to make a Makefile, to compile service software, and to create a service software library.
(B) The digital television receiving device modifies the Makefile, creates a digital television receiving device software library and an interface adaptation module library.
(C) The digital television receiving device links the service software library, the digital television receiving device software library, and the interface adaptation module library into an object file, and generates an executable file.
(D) The executable file is multiplexed into a Transport Stream (TS) via an upgrade server according to a predefined protocol.
(E) An upgrade module of the digital television receiving device software receives and extracts the data, and assembles a new upgrade file;
(F) The new upgrade file is written into a nonvolatile memory (e.g., a FLASH).
Apparently, in the conventional technical solution, the digital television receiving device software has to be upgraded together with the service software. However, the digital television service provider has a much higher demand for software upgrades than the digital television receiving device provider. In consideration of the inconvenience of the subscribers experienced during the upgrade process, the digital television receiving device provider is often unwilling to upgrade the software, or is unwilling to provide assistance to the digital television service provider to upgrade the software. Undoubtedly, this may cause unnecessary troubles in the development of digital television services. Due to the fact that the digital television receiving device software has to be upgraded at the same time when the service software is upgraded, the service software provider is restricted by the digital television receiving device provider sometimes. In addition, in the case of a narrow bandwidth, it will take a long time to upgrade the software, resulting in a poor experience of the subscriber, and the bandwidth of the multiplexer will be wasted.